Manufacture of spirally-corrugated sheet-metal spheroids



(No Model.)

B. GOTHBERG, MANUFACTURE OF SPIRALLY CORRUGATED SHEET METAL SPHEROIDS."No. 425,099. Patented Apr. 8, 1890.

UNITED STATES PATENT OFFICE.

MANUFACTURE OF SPlRALLY-CORRUGATED SHEET-METAL SPHEROIDS.

SPECIFICATION forming part of Letters Patent No. 425,099, dated AprilApplication filed February 10, 1890. Serial 110.339,?)5'7. (No model.)

To 00% whom it may concern:

Be it known that I, ERNST GOTHBERG, of Jersey City, in the county ofHudson and State of New Jersey, have invented certain new and usefulImprovements in the Manufacture of spirally-Corrugated Sheet-MetalSpheres and Spheroids for Ornamental Purposes, and I do hereby declarethat the following is a full and exact description thereof, referencebeing had to the accompanying drawings, and to the letters of referencemarked thereon, making a part of this specification.

My invention relates to the formation of spirally corrugated spheroidalbodies of sheet metal for various ornamental purposes. Heretofore suchsheet-metal spheroids have been formed in two divisions parted upon aline transversely to the length of the corrugations and the axis of thebody. In such case the transverse joint or seam between the twodivisions produces a break in the continuity of the curved lines of thecorrugations, which greatly mars the ornamental effect thereof.

The object of my invention is to produce an ornamental spheroid of sheetmetal indented with a series of spiral corrugations, each of which shallbe continuous from the one pole to the other, so as to present in reliefwith a smooth uniform surface a continuous series of spiralcorrugations, forming in cross-section a series of deep regular curvesof uniform radii.

It consists in the method, substantially as hereinafter described andclaimed, of building up the spheroid in segmental divisions or sectionswhose joints are made to coincide with the curves of the spiralcorrugations, and are thereby so concealed as not to mar the unity ofthe design and the continuity of outline in the outer configuration ofthe spheroid.

In the accompanying drawings, Figure 1 is an elevation of aspirally-corrugated ball of sheet metal made in pursuance of myinvention; Fig. 2, a crosssection thereof in line a: 00 of Fig. 1 withsome of the divisions of the ball removed, their normal position beingindicated by dotted lines; Fig. 3, a plan view of one of the dies bywhich the sections of the ball are formed; and Fig. 4?, a sectional Viewillustrating the two forming-dies when closed upon the metal sheet.

The complete ball represented in'Fig. 1 is formed by the union of aseries of similar segmental sections A A A, each so flutedlongitudinally with corrugations following ogee curves as to form spiralindentations and intervening elevations in the direction of the lengthof the segment, and each bounded laterally by said curves, as shown inFigs. 1 and 2. A narrow flange D is formed upon one edge of each sectionto overlap the counterpart edge of the next section, and since theseedges follow the spiral curves of the corrugations the overlapping jointwhich they form does not break the continuity of the curved lines uponthe periphery of the ball, .but by harmonizing therewith is concealedthereby.

Each of the segmental spirally-corrugated sect-ions A A is formed bystamping a suitable piece of sheet metal between a pair of cameo andintaglio dies B B, operated by a press in the customary manner, so as tonot only impart thereto a concave-convex shape, but also form a seriesof longitudinal indentations e and intervening elevations f, followingthe ogee or spiral curves of the edges of the piece, the flange D uponone edge serving to make a joint between each section and the next inorder. These corrugations, which constitute the ornamental feature ofthe finished sphere or spherical spheroid, are preferably made topresent a uniform curve in cross-section, as shown in Fig. 2. Theseveral similar sections thus stamped up between the dies are thenunited bycausing the flanged edge D of each section to overlap theopposite edge t' of the next, as shown in Fig. 2, and fixing the samewith solder or by rivets, the sections being so proportioned in theirdimensions as that a given number will, when assembled and join ed inmanner as described, produce an exact sphere or spheroid. The ends ofthe sections are preferably flanged, as at H, each in a segmental curve,so as to leave an opening at each end of the ball, the flanges I1forming, when the sections are assembled, a collar encircling theopening, as shown in Fig. 1.

It is evident that the spirally-corrugated body thus produced may bemore or less elongated, and may also be made of an oblate or pear shape.

1 claim as my invention 1. The method, substantially as hereindescribed, of forming spherical bodies, which consists in first stampingpieces of sheet metal between suitable dies, each into a concave-convexform, embracing the segment of a sphere or spheroid having longitudinaledges following ogee or spiral curves and its body longitudinally flutedin corrugations conforming to said edges, and then assembling and fixingsaid segmental spirally-corrugated seotions so that the edge of the onesection shall overlap the opposite edges of the adjacent section.

ERNST GO'IIIBERG.

\Vitnesses:

A. N. .TEsBERA, E. M. \VATSON.

